Newborns that need special care are placed in a specialized area, such as a neonatal intensive care unit (NICU) within a hospital. Pre-, post and term sick newborns that require a special environment are kept in an incubator (at temperatures up to 39 deg C., humidity up to 100% and oxygen up to 100%), and can be coupled to several life sustaining devices (e.g., a ventilator for artificial breathing, transfusion pumps for delivering the exact amount of fluids necessary for survival of the newborn, intra-venous (I/V) bags for delivering saline or glucose, etc.). Additionally, vital signs monitoring equipment (e.g., electrocardiogram (ECG), electroencephalogram (EEG), blood saturation oxygen levels, carbon dioxide build up levels, blood pressure, body temperature, etc.), which generally have several lines (e.g., monitoring lines for ECG, EEG, O2, CO2, temperature and pressure), are coupled to the newborn at all times for continuous care and monitoring.
Severely ill newborns that demand special care generally are left in the NICU and are not transported to other hospital sections for diagnostic procedures, such as X-ray, computer tomography (CT), magnetic resonance (MR), etc. Additionally, clinical interventions, such as radiation therapy for cancer patients, cardiac catheterization for patients with compromised cardiovascular systems, and minimally invasive surgery procedures in or near the diagnostic scanners also are generally not performed on severely ill newborns. Thus, diagnosis and treatment is limited to moderately ill newborns and generally is not extended to severely ill newborns. This is unfortunate.
Magnetic resonance is a premier diagnostic tool and is used routinely in the characterization of illness in the first few hours of life. Newborns with illness of the brain, heart or major organs in the torso and pelvis (e.g., liver, kidney, spleen, etc.) are often transported in a regular non-MR compatible transport incubator to the MR system. Prior to being scanned in the MR system, the life sustaining and monitoring lines of the transport incubator are uncoupled from the newborn, and a local set of lines are re-coupled to the newborn. The patient then is removed from the transport incubator and placed on a magnetic resonance imaging (MRI) table. Subsequently, the patient is imaged in a super cooled MR scanner using adult sized radio-frequency (RF) coils. Once the imaging procedure is completed, the patient is placed back in the transport incubator, the local lines are uncoupled, the transport incubator lines are re-coupled, and the patient is transported back to the NICU in the transport incubator. Clearly, the newborn's environment is disturbed on multiple occasions prior to, during and after an MR scan.
Moreover, because of the disturbance to the newborn's environment, patients with compromised thermoregulatory systems are rarely scanned due to their need for a highly controlled environment. This necessitates that a controlled environment (e.g., an incubator) be provided along with all the life sustaining and vital signs monitoring equipment during all stages of the MR scan, including transport to the MR system, the MR scan, and transport back to the NICU.
Diagnosis/prognosis using MR depends on MR image quality. Newborns placed in adult sized coils have a low filling factor, which results in low signal-to-noise ratios (SNRs). Given the smaller physical size of newborns, higher imaging resolutions are sought in smaller volumes, which further reduce the SNR. Custom RF coils are sought to address the loss in SNR and to reduce the stay of the newborn in the MR scanner.
Accordingly, an incubator used in MR scanning should not adversely affect the image quality produced from an MR scan. Moreover, to protect the patient's health and safety, the MR scanner must not adversely affect the operation of the incubator.
An incubator for tomographic examination was disclosed by Koch et al. (U.S. Pat. No. 5,800,335 issued Sep. 1, 1998), and is of a modular design. This incubator, however, fails to encompass a complete sub-system. For example, the incubator disclosed in Koch et al. requires additional components to transport an infant to/from the MR scanner and does not include life sustaining equipment or vital signs monitoring equipment. Additionally, while the incubator design is novel, the heater switching circuitry can produce artifacts during MR scanning and, therefore, degrade the image quality of the MR scan. Furthermore, during imaging the incubator is placed inside an RF coil, which results in a low filling factor, thus degrading the image quality.
The concept of an RF coil inside an incubator was introduced by Nordell et al. (see International Publication Number WO98/48756 A1, issued Nov. 5, 1998). More particularly, a receive only RF coil was introduced inside the incubator for effective scanning. Fluid flow turbines or related technology circulate the air inside the incubator to achieve even temperatures in the incubator volume. A stand-alone monitor in the base unit, which is situated near the MR patient table, monitors and displays the patient's vital signs. Vital signs monitoring lines typically span from the MR patient table, where the patient is placed, to the base unit at the foot of the MR patient table inside the MR room. The unit worked as proposed, but the long line spans hampered efficient performance as they obstructed patient care. For example, when immediate access to the patient was sought, one had to juggle his/her way through the maze of lines.
A novel solution to this problem was addressed by Rohling et al. (U.S. Pat. No. 6,611,702 issued Aug. 26, 2003) wherein the entire incubator and monitoring unit are built on a General Electric (GE) MR patient table. The unit, however, is bulky and difficult to maneuver, particularly in a hospital environment. Generally, a minimum of three people are required to maneuver the unit from the NICU to the MR section. Additionally, the incubator is not modular and the entire unit must be transported together, which limits access to certain sections of the hospital.
Recently an application for patent for an MR compatible incubator/transporter system was filed by Lonneker-Lammers (see EP20010109195 20010412, filed April 2002 and WO 02-083053A1, filed Apr. 12, 2002). With this MR compatible incubator system, safe transport is possible between the NICU and the MR sections, and the patient is left undisturbed from the time he/she is transported from the NICU to the MR scanner, during the MR scan, and transported back to the NICU. Improvements to the RF coil design for high SNR were made by Srinivasan (U.S. Application Ser. No. 60/722,760 filed Nov. 26, 2003).
The above described systems, however, do not provide a complete solution for newborn care, transport and MR scanning. Accordingly, there is a need in the art for a self-contained neonate imaging sub-system, including an MR compatible incubator, MR compatible life sustaining and monitoring equipments, MR compatible ventilator, MR compatible infusion pumps, MR compatible injectors, and high SNR RF coils, all of which can be used to care for, to transport, to perform clinical interventions and to image the patient without significantly disturbing the microenvironment of the incubator.